Alright, I'll preface this with...I don't own one.
On the other hand, a good friend had given me the take off barrel from his, when he switched to a .17 Fireball, and the end result was that he ended up asking me, rather hang-dog-ish, for it back. Which he got, along with my laughter and a reminder that I HAD actually asked him if he was SURE he wanted to give the barrel away!
Buy the wrench, do it yourself, keep the wrench and the barrel tucked into a corner of the safe, and you can always go back, or add it into the pile when you sell the rifle.
Jerry at Mystic Precision, IIRC, had posted the technique he uses to install his own barrels without using a actual gage, where he uses a 'reference' cartridge he keeps for the purpose, and adjusts the barrel in to contact, then backs off a determined amount to set his headspace. He is not the only one I had read that uses the method.
It ain't brain science, it's more like rocket surgery, eh?

Maybe a little less complicated than that!
Cheers
Trev